45342

Appears in sequences

• Number of 3 X n 0..1 arrays with diagonals and antidiagonals unimodal and rows nondecreasing.at n=39A223950
• Practical numbers m with m-1 and m+1 both prime, and prime(m)-1 and prime(m)+1 both practical.at n=11A257922
• Irregular table read by rows: Place n equally spaced points on the circumference of a circle of radius r and then connect each pair of points with straight lines whose intersections create A007569(n) - n additional points. Draw a circle of radius r around each of the A007569(n) points. T(n,k) is the number of k-sided regions, k>=2, formed from all circle intersections.at n=49A374828